Display substrate and display panel having the same

ABSTRACT

In a display substrate and a vertical alignment display panel having the same, the display panel includes an array substrate and an opposite substrate. A plurality of first slit portions are arranged through a pixel area of a common electrode on the array substrate, and the first slit portions extend in a slanted direction. A plurality of grooves and a plurality of protruding portions are alternately arranged at edges facing each other on the first slit portion, so that the first slit portions are patterned. A positive singular point is generated on a side surface of a protruding portion, and a negative singular point is generated between the positive singular points.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority from and the benefit of Korean PatentApplication No. 2008-67540, filed on Jul. 11, 2008, which is herebyincorporated by reference for all purposes as if fully set forth herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a display substrate and a display panelhaving the display substrate. More particularly, exemplary embodimentsof the present invention relate to a display substrate used as asubstrate of a vertical alignment (VA) liquid crystal display (LCD)panel and a VA LCD panel having the display substrate.

2. Discussion of the Background

Generally, a liquid crystal display (LCD) device is one of the mostwidely used types of flat panel display devices. An LCD device includestwo display substrates having electrodes forming an electric field and aliquid crystal layer formed between the two display substrates. Avoltage is applied to each of the electrodes to rearrange liquid crystalmolecules, so that the transmissivity of light passing through theliquid crystal layer is controlled.

The electrodes forming an electric field are respectively formed on thedisplay substrate. Specifically, a plurality of pixel electrodes isarranged in a line on the display substrate, and a common electrodecovers the other substrate. A voltage is applied to each of the pixelelectrodes to display an image on the LCD device. A switching element,which is a three-terminal device, is connected to each pixel electrodefor switching a voltage applied to the pixel electrode. A gate linetransmits a signal to control the switching element, and a data linetransmits a voltage that is applied to the pixel electrode. The gateline and data line are formed on the display substrate.

However, an LCD device is disadvantageous in that it may have a narrowviewing angle. Various technologies have been developed to overcome thisproblem. For example, liquid crystal molecules may be vertically alignedwith respect to two substrates, and a slit portion pattern or aprotrusion pattern may be formed on a pixel electrode and a commonelectrode facing the pixel electrode to divide a pixel into multipledomains.

However, in the vertical alignment (VA) LCD device having slit portionpatterns or protrusion patterns, afterimages and spots may be generatedin the slit portion patterns or protrusion patterns. Moreover, when ascreen is rubbed, spots may be generated.

SUMMARY OF THE INVENTION

The present invention provides a display substrate that may be capableof preventing afterimages and spots.

The present invention also provides a display panel having the displaysubstrate.

Additional features of the invention will be set forth in thedescription which follows, and in part will be apparent from thedescription, or may be learned by practice of the invention.

The present invention discloses a display substrate that includes a basesubstrate and a transparent electrode. The base substrate includes apixel area with a horizontal side and a vertical side. A transparentelectrode is disposed in the pixel area and includes a plurality of slitportions extending in a slanted direction with respect to the horizontalside and the vertical side. A first edge of the slit portions comprisesa first groove and a first protruding portion that are alternatelyarranged, and the first protruding portion is defined by adjacent firstgrooves. A second edge of the slit portions faces the first edge andincludes a second protruding portion corresponding to the first groove,and a second groove corresponding to the first protruding portion. Thesecond protruding portion and the second groove are alternatelyarranged.

The present invention also discloses a display panel that includes anarray substrate, an opposite substrate and a liquid crystal layer. Thearray substrate includes a lower substrate, a switching element, asignal line and a pixel electrode. The switching element is arranged onthe lower substrate. The signal line is connected to the switchingelement. The pixel electrode is connected to an output electrode of theswitching element. The opposite substrate includes an upper substrateand a common electrode. The upper substrate has a pixel area with ahorizontal side and a vertical side. The common electrode has aplurality of slit portions. The common electrode extends in a slanteddirection with respect to the horizontal side and vertical side. Aplurality of grooves and a plurality of protruding portions defined bythe grooves are alternately arranged in edges facing each other of thefirst slit portion so that the first slit portions have a zigzag patternshape defined by the groove and the protruding portion. The liquidcrystal layer is arranged between the array substrate and the oppositesubstrate to be vertically aligned with respect to the array substrateand the opposite substrate.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention, andtogether with the description serve to explain the principles of theinvention.

FIG. 1 is a plan view showing a display panel according to a firstexemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line I-I′ of FIG. 1.

FIG. 3 is a plan view showing an opposite substrate of FIG. 2.

FIG. 4 is an enlarged view showing a first slit portion of FIG. 3.

FIG. 5 is an enlarged view showing a bent portion of a first slitportion of FIG. 3.

FIG. 6 is a plan view showing an array substrate of FIG. 2.

FIG. 7A, FIG. 7B, and FIG. 7C are cross-sectional views showing aprocess for manufacturing the opposite substrate of FIG. 2 and FIG. 3.

FIG. 8 is a plan view showing a display panel according to a secondexemplary embodiment of the present invention.

FIG. 9 is a plan view showing a display panel according to a thirdexemplary embodiment of the present invention.

FIG. 10A, FIG. 10B, and FIG. 10C are cross-sectional views showing aprocess for manufacturing the array substrate of FIG. 9.

FIG. 11 is a plan view showing a display panel according to a fourthexemplary embodiment of the present invention.

FIG. 12 is a plan view showing a display panel according to a fifthexemplary embodiment of the present invention.

FIG. 13 is a cross-sectional view taken along line II-II′ of FIG. 12.

FIG. 14 is a cross-sectional view showing a display panel according to asixth exemplary embodiment of the present invention.

FIG. 15 is a cross-sectional view showing a display panel according to aseventh exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

The invention is described more fully hereinafter with reference to theaccompanying drawings, in which embodiments of the invention are shown.This invention may, however, be embodied in many different forms andshould not be construed as limited to the embodiments set forth herein.Rather, these embodiments are provided so that this disclosure isthorough, and will fully convey the scope of the invention to thoseskilled in the art. In the drawings, the size and relative sizes oflayers and regions may be exaggerated for clarity. Like referencenumerals in the drawings denote like elements.

It will be understood that when an element or layer is referred to asbeing “on” or “connected to” another element or layer, it can bedirectly on or directly connected to the other element or layer, orintervening elements or layers may be present. In contrast, when anelement is referred to as being “directly on” or “directly connected to”another element or layer, there are no intervening elements or layerspresent.

It will be understood that, although the terms first, second, third etc.may be used herein to describe various elements, components, regions,layers and/or sections, these elements, components, regions, layersand/or sections should not be limited by these terms. These terms areonly used to distinguish one element, component, region, layer orsection from another region, layer or section. Thus, a first element,component, region, layer or section discussed below could be termed asecond element, component, region, layer or section without departingfrom the teachings of the present invention.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the exemplary term “below” can encompass both anorientation of above and below. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting of thepresent invention. As used herein, the singular forms “a,” “an” and“the” are intended to include the plural forms as well, unless thecontext clearly indicates otherwise. It will be further understood thatthe terms “comprises” and/or “comprising,” when used in thisspecification, specify the presence of stated features, integers, steps,operations, elements, and/or components, but do not preclude thepresence or addition of one or more other features, integers, steps,operations, elements, components, and/or groups thereof.

Exemplary embodiments of the invention are described herein withreference to cross-sectional illustrations that are schematicillustrations of idealized exemplary embodiments (and intermediatestructures) of the present invention. As such, variations from theshapes of the illustrations as a result, for example, of manufacturingtechniques and/or tolerances, are to be expected. Thus, exemplaryembodiments of the present invention should not be construed as limitedto the particular shapes of regions illustrated herein but are toinclude deviations in shapes that result, for example, frommanufacturing. For example, an implanted region illustrated as arectangle will, typically, have rounded or curved features and/or agradient of implant concentration at its edges rather than a binarychange from implanted to non-implanted region. Likewise, a buried regionformed by implantation may result in some implantation in the regionbetween the buried region and the surface through which the implantationtakes place. Thus, the regions illustrated in the figures are schematicin nature and their shapes are not intended to illustrate the actualshape of a region of a device and are not intended to limit the scope ofthe present invention.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art andwill not be interpreted in an idealized or overly formal sense unlessexpressly so defined herein.

Hereinafter, exemplary embodiments of the present invention will beexplained in detail with reference to the accompanying drawings.

FIG. 1 is a plan view showing a display panel according to a firstexemplary embodiment of the present invention. FIG. 2 is across-sectional view taken along line I-I′ of FIG. 1.

Referring to FIG. 1 and FIG. 2, a display panel 100 includes an arraysubstrate 101, an opposite substrate 105, and a liquid crystal layer108.

The opposite substrate 105 and the array substrate 101 are disposedfacing each other, the liquid crystal layer 108, which includes liquidcrystal molecules 209, is interposed between the opposite substrate 105and the array substrate 101. A lower alignment layer 102 and an upperalignment layer 202, which contact the liquid crystal layer 108, areformed on the array substrate 101 and the opposite substrate 105,respectively. The liquid crystal molecules 209 are induced to besubstantially perpendicular to the array substrate 101 and the oppositesubstrate 105 by the lower alignment layer 102 and an upper alignmentlayer 202 in a state in which an electric field is not applied to theliquid crystal layer 108, that is, the liquid crystal molecules 209 arealigned vertically with respect to the array substrate 101 and theopposite substrate 105. Outward sides of the opposite substrate 105 andthe array substrate 101 are attached to an upper and lower polarizer,respectively.

A display substrate according to the first exemplary embodiment of thepresent invention, that is, the opposite substrate 105, includes anupper substrate 107, a light-blocking pattern 210 formed on the uppersubstrate 107, a color filter 230, an overcoating layer 250, and acommon electrode 270.

The upper substrate 107 includes a pixel area PA, which transmits light,and a light-blocking area SA, which blocks light and surrounds the pixelarea PA. The pixel area PA has a horizontal side and a vertical side.The pixel area PA has a substantially rectangular shape.

The color filter 230 is formed in the pixel area PA. The color filter230 includes a red filter, a green filter, and a blue filter.Substantially identical color filters 230 are formed on the plurality ofpixel areas PA arranged in a horizontal direction X, and different colorfilters 230 are formed on the plurality of pixel areas PA arranged in avertical direction Y.

The light-blocking pattern 210 is formed on the light-blocking area SAto surround the red filter, the green filter, and the blue filter.

The overcoating layer 250 covers the light-blocking pattern 210 and thecolor filter 230.

FIG. 3 is a plan view showing the opposite substrate 105 of FIG. 2.

Referring to FIG. 1 and FIG. 3, the common electrode 270 is formed onthe overcoating layer 250. The common electrode 270 is formed from atransparent conductive material such as indium tin oxide (ITO) or indiumzinc oxide (IZO). A plurality of the first slit portions 271 are formedthrough the common electrode 270. The first slit portions 271 may beopenings formed through the common electrode 270. An opening width ofthe first slit portion 271 may be a few μm to a few tens of μm.

The first slit portion 271 is extended in a slanted direction Z withrespect to the horizontal side and vertical side in the pixel area PA.The common electrodes 270 are spaced apart from each other. Certain slitportions among the first slit portions 271 may include bent portionsbent parallel with the vertical sides. Other certain slit portions amongthe first slit portions 271 may include bent portions bent parallel withthe vertical sides and the horizontal sides, respectively.

The first slit portion 271 is formed through the common electrode 270 tobe symmetrical with respect to a center line C-C′, which is the centerline of the horizontal side in the pixel area PA. Accordingly, thecertain first slit portions 271 formed through the pixel area PA may bearranged in a V-shape. Alternatively, two of the first slit portions 271different from each other are crossed at the center line C-C′ and aportion of the first slit portion 271 extends in parallel with thecenter line C-C′. Two of the first slit portions 271 may be arranged ina Y-shape.

The edges 272 and 274 facing each other of the first slit portion 271have a convex and concave pattern. For example, the edges 272 and 274have a groove 273 and a protruding portion 275 formed in an alternatingarrangement. The protruding portion 275 is defined by the two of grooves273 that are adjacent to each other. Accordingly, the depth of thegroove 273 is substantially identical to the height of the protrudingportion 275. Also, a side surface of the protruding portion 275 issubstantially identical to a side surface of the groove 273. The depthof the groove 273 and the height of the protruding portion are formed ofa definite depth or height, for example, about 2 μm to 4 μm.

The depth and height represent a depth and a height in a width directionof the first slit portion 271 substantially perpendicular to the slanteddirection Z.

In this embodiment, a side surface of the groove 273, that is, a sidesurface of the protruding portion 275 is substantially perpendicular tothe slanted direction Z. That is, an edge of the protruding portion 275is substantially perpendicular-edged.

The first edge 272 and second edge 274 face each other on the first slitportion 271. Accordingly, the groove 273 and the protruding portion 275are formed in an alternating arrangement at the first edge 272 and thesecond edge 274, respectively.

A first groove 273 formed at the first edge 272 corresponds to thesecond protruding portion 275 formed at the second edge 274, a firstprotruding portion 275 formed at the first edge 272 corresponds to asecond groove 273 formed at the second edge 274.

The length of the first and second grooves 273 in a slanted direction Zis longer than the length of the first and the second protrudingportions 275 in a slanted direction Z. The first and the secondprotruding portions 275 are not interposed in the second and the firstgroove 273. Alternatively, the first and the second protruding portions275 may be interposed in the second and the first groove 273.

The first and second groove 273, and the first and the second protrudingportions 275 are disposed in an alternating arrangement with each otheras described above, so that the first slit portion 271 has a zigzagpattern in the slanted direction Z when viewed as a whole. A sidesurface of the first groove 273 and a side surface of the secondprotruding portion 275 corresponding to the first groove 273 are facingeach other. A side surface of the first groove 273 and a side surface ofthe second protruding portion 275 correspond to a position where thefirst slit portion 271 is bent. Hereinafter, the first slit portion 271of the bent position is called a bent portion.

The first slit portions 271 divide the pixel area PA into a plurality ofdomains. A generating position of singular point SP is uniform by a bentportion of the first slit portions 271 on a liquid crystal layer 108arrayed in the domains.

The singular point SP is defined as a singular point where anarrangement of liquid crystal is suddenly changed to directionsdifferent from that of a peripheral liquid crystal molecule 109 and doesnot have a specific direction. The singular point is known to begenerated in a position where an electric field becomes stronger orweaker than the surrounding electric field.

A positive singular point is formed in a position where an electricfield is stronger than the surrounding electric field. The positivesingular point is generated where a liquid crystal director is gatheredinto a point. A negative singular point is formed in a position where anelectric field is weaker than the surrounding electric field. Thenegative singular point represents where the liquid crystal is spreadinto a radial shape. In addition, the positive singular point and thenegative singular point are alternately formed.

Liquid crystal may not be able to block light at a singular point, and agenerating position of the singular point is non-uniform, which resultsin formation of afterimages and spots on a displayed image by a displaypanel 100. A display device according to the present invention controlsa generating position of the singular point, so that the singular pointmay be regular in the pixel area PA, which may prevent generation ofafterimages and spots.

FIG. 4 is an enlarged view showing a first slit portion 271 of FIG. 3.

Referring to FIG. 3 and FIG. 4, as a result of a simulation with regardto a display panel 100 according to an exemplary embodiment of thepresent invention, an electric field is enhanced more than thesurrounding electric field to form a positive singular point on the bentportion of the first slit portions 271. Also, between the bent portions,that is, an electric field is weaker than the surrounding electric fieldto form a negative singular point on a position corresponding to thecenter of the groove 273 or the center of the protruding portion 275 ina slanted direction Z.

Accordingly, a generating position of a singular point of liquid crystalis definite on all of pixel area PA, so that afterimages and spots arenot formed.

Alternatively, as described above, the first slit portion 271substantially disposed of Y-shape is crossed at the center line C-C′.The crossing position is defined as a divergence point. A negativesingular point is generally formed at the divergence point. Accordingly,a function of the divergence point is substantially identical to aposition corresponding to a position between the bent portions withregard to controlling a singular point of liquid crystal.

To control a singular point of liquid crystal by the groove 273 and theprotruding portion 275 effectively, the length of the groove 273 and theprotruding portion 275 in a slanted direction Z may be properlycontrolled.

The length of the groove 273 and the protruding portion 275 in a slanteddirection Z may about 60 μm to 90 μm. When the length is less than 60 μmor more than 90 μm, a generating position of a singular point of theliquid crystal may be non-uniform. Alternatively, the length of thegroove 273 and the protruding portion 275 in a slanted direction Z maydepend on the size of the pixel area PA.

FIG. 5 is an enlarged view illustrating a bent portion of a first slitportion 271 of FIG. 3.

Referring to FIG. 3 and FIG. 5, as described above, a bent portion ofthe first slit portion 271 is bent parallel with the horizontal side orthe vertical side. A bent portion of the first slit portion 271 parallelwith the vertical side is shown in FIG. 5.

As a result of the simulation, a negative singular point is generated ata bent portion of the first slit portion 271. Accordingly, a function ofa bent portion of the first slit portion 271 is substantially identicalto a position corresponding to a position between the bent portions withregard to inducing a singular point of liquid crystal.

Alternatively, the closest singular point from a bent portion of thefirst slit portion 271 is a positive (+) singular point. Accordingly, itis preferable that the bent portion is adjacent to the horizontal sideor a vertical side having a bent portion of the first slit portion 271disposed thereon. When the bent portion is far from a bent portion ofthe first slit portion 271, a forming portion of a singular pointbetween a bent portion of the first slit portion 271 and the bentportion may be non-uniform.

FIG. 6 is a plan view illustrating an array substrate 110 of FIG. 2

Referring to FIG. 1, FIG. 2, and FIG. 6, an array substrate 101 includesa lower substrate 103, a gate line 111 formed on the lower substrate103, a data line 121, a maintenance electrode 131, a switching element140, an insulation layer 160, and a pixel electrode 170.

The gate line 111 may apply a gate signal to the switching element 140from an external signal source. The gate line 111 is formed on the lowersubstrate 103, and extends toward the horizontal side of the pixel areaPA. A portion of each gate line 111 forms a plurality of gate electrodes112. A contacting pad that applies the gate signal may be formed on abent portion of the gate line 111. Alternatively, a bent portion of thegate line 111 may be directly connected to an output terminal of a gatedriving circuit portion disposed on the lower substrate 103.

The maintenance electrode 131 is formed on the same layer of the lowersubstrate 103 as the gate line 111. The maintenance electrode 131 isdisposed corresponding to the divergence point of the first slit portion271 on the opposite substrate 105. Accordingly, the maintenanceelectrode 131 is disposed between adjacent gate lines 111.

A gate insulation layer 119 covers the gate line 111 and the maintenanceelectrode 131.

A plurality of the data lines 121 and a drain electrode 145 extendedtoward a vertical side are formed on the gate insulation layer 119. Abent portion of the drain electrode 145 corresponds to the center of thegroove 273 or the protruding portion 275 formed on the first slitportion 271 in the slanted direction Z.

A source electrode 141 protrudes from the data line 121 toward the drainelectrode 145. A lower portion of the data line 121 and the drainelectrode 145 include a linear shape semiconductor layer 142 thatgenerally extends in the vertical direction along the data line 121 Thelinearly shaped semiconductor layer 142 corresponds to the gateelectrode 112, and has a channel layer overlapped with the sourceelectrode 141 and the drain electrode 145.

The gate electrode 112, the gate insulation layer 119, the channellayer, the source electrode 141, the semiconductor layer 142, and thedrain electrode 145 compose the switching element 140.

The insulation layer 160 covers the switching element 140 and the dataline 121. A contact hole 161 is formed through the insulation layer 160so that the contact hole exposes a portion of a bent portion of thedrain electrode 145 Accordingly, the contact hole 161 may correspond tothe center of the groove 273 or the protruding portion 275 formed on thefirst slit portion 271 in the slanted direction Z.

As a result of the simulation, it is recognized that a negative singularpoint is generated in a stepped groove formed in the insulation layer160. Due to the contact hole 161, the insulation layer 160 is formed ina stepped shape.

Accordingly, when the contact hole 161 corresponds to the center of thegroove 273 or the protruding portion 275 on the first slit portion 271in the slanted direction Z between the first slit portion 271 and thegroove 273, a negative singular point may be fixedly formed on thecontact hole 161, so that a singular point may be formed at apredetermined position.

The pixel electrode 170 is formed on the insulation layer 160, and isconnected to the drain electrode 145 through the contact hole 161. Asecond slit portion 171 is formed through the pixel electrode 170. Thesecond slit portion 171 extends in a slanted direction Z, and isdisposed between the first slit portions 271. As a result, the pixelarea PA is divided into a plurality of domains as described above.

The second slit portions 171 may be disposed to be symmetrical withrespect to the center line C-C′ in the horizontal direction similar tothe first slit portions 271.

A stepped groove corresponding to the maintenance electrode 131 may beformed in the insulation layer 160 to increase a maintenance capacity byreducing the distance between the maintenance electrode 131 and thepixel electrode 170.

As described above, the maintenance electrode 131 is disposedcorresponding to the divergence point on the first slit portion 271. Asdescribed above, a negative singular point is generated by the steppedgroove 165 formed in the insulation layer 160. Also, a negative singularpoint of liquid crystal is generated by the divergence point.Accordingly, a negative singular point may be definitely generated onthe stepped groove or the divergence point, and as a result, a positionof a positive singular point may be fixedly controlled.

The liquid crystal layer 108 is aligned in a vertical direction betweenthe opposite substrate 105 and the array substrate 101. The liquidcrystal layer 108 includes the liquid crystal 209. An arrangement angleof the liquid crystal 209 is changed by an electric field formed betweenthe pixel electrode 170 and the common electrode 270.

The first slit portion 271 formed through the common electrode 270 andthe second slit portion 171 formed through the pixel electrode 170causes a distortion of the direction of an electric field to rearrange adirector of the liquid crystal 209. Accordingly, the directors of theliquid crystal 209 are different from each other on a plurality ofdomains to improve a side viewing angle.

As described above, a singular point of the liquid crystal 209 isconstantly generated on the bent portion of the first slit portion 271,between the bent portions, a bent portion of the first slit portion 271,and a divergence point of the first slit portion 271 in the pixel areaPA. Accordingly, a difference by a non-uniform generation of a singularpoint between the pixels may not be recognized. Thus, the displayquality of a display device may be improved due to the non-recognitionof afterimages or spots.

A display substrate and a display panel 100 of the present invention maybe employed in all types of vertical alignment (VA) liquid crystaldisplay (LCD) panels 100. That is, when an electrode which controls theliquid crystal 209 is patterned and the liquid crystal 209 of an LCDpanel is vertically aligned, it is employed in any cases that are notrelevant to whether a position of the color filter 230 is on theopposite substrate 105 or the array substrate 101, and whether theinsulation layer 160 is formed on the array substrate 101. Accordingly,it will be apparent that the modified examples are within thetechnological scope of the present invention.

FIG. 7A, FIG. 7B, and FIG. 7C are cross-sectional views illustrating aprocess for manufacturing the opposite substrate of FIG. 2 and FIG. 3. Adisplay panel manufactured by the processes shown in FIG. 7A, FIG. 7B,and FIG. 7C is substantially identical to the opposite substrate 105described in FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5, and FIG. 6.Accordingly, the same reference numerals will be used to refer to thesame elements as those described.

To manufacture the display substrate 101, as well as the oppositesubstrate 105, as shown in FIG. 7A, a light-blocking material layer isdeposited on the upper substrate 107, and is patterned to form thelight-blocking pattern 210 on the light-blocking area SA.

Then, a color photoresist layer is deposited in the pixel area PAdefined by the light-blocking pattern 210, and then the colorphotoresist layer is patterned to form the color filter 230. Then, aresin is formed to cover the color filter 230 and the light-blockingpattern 210 to form the overcoating layer 250.

Then, an optically transparent and electrically conductive material suchas ITO or IZO is formed on the overcoating layer 250 to form a commonelectrode layer (not shown). Then, the common electrode layer ispatterned to form the common electrode 270 having the first slitportions 271 formed therethrough, as shown in FIG. 7B.

Then, as shown in FIG. 7C, an upper alignment layer 202 covering thecommon electrode 270 is formed to complete the opposite substrate 105.

The opposite substrate 105 and the array substrate 101 are combined witheach other, and then the liquid crystal layer 108 is interposed betweenthe opposite substrate 105 and the array substrate 101 to manufacturethe display panel 100.

A process of forming the array substrate 101 is substantially identicalto a following explanation in the third exemplary embodiment. Thus, anydetailed explanation concerning a process of forming the array substratewill be alternated to a following explanation.

FIG. 8 is a plan view illustrating a display panel according to a secondexemplary embodiment of the present invention.

Referring to FIG. 8, a display panel 400 in this embodiment issubstantially identical to the display panel 100 described in FIG. 1,FIG. 2, FIG. 3, FIG. 4, FIG. 5, FIG. 6, FIG. 7A, FIG. 7B, and FIG. 7Cexcept that the shape of a groove 573 and a protruding portion 575 isaltered, in which the groove 573 and the protruding portion 575 areformed through the first slit portion 571 on an opposite substrate.Thus, the same reference numerals will be used to refer to the sameelements as those described, and any detailed explanation will beomitted.

A display substrate 500 in this embodiment, that is, the oppositesubstrate 501 is substantially identical to the opposite substratedescribed in FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5, FIG. 6, FIG. 7A,FIG. 7B, and FIG. 7C except for the shape of a groove 573 and aprotruding portion 575 formed through the first slit portion 571. Thus,the same reference numerals will be used to refer to the same elementsas those described, and any detailed explanation will be omitted.

In this embodiment, the common electrode 570 on the opposite substratehas a first slit portion 571 formed therethrough, as described above,edges facing each other of the first slit portion 571 have a groove 573and a protruding portion 575 formed in an alternating arrangement sothat the protruding portion 575 is defined by adjacent grooves 573. Theedges facing each other have the groove 573 and the protruding portion575 formed facing each other in an alternating arrangement.

In this embodiment, a side surface of the groove 573, that is, a sidesurface of the protruding portion substantially forms an angle of about45 degrees in the slanted direction Z extended from the first slitportion 571. That is, the protruding portion 575 may have a trapezoidalshape.

When this embodiment is compared with the first exemplary embodiment inwhich a side surface of the protruding portion 575 forms an angle ofabout 90 degrees in the slanted direction Z, it is recognized that thestability of generating a singular point of the liquid crystal in apredetermined position is similar to the first exemplary embodiment.

In this embodiment, a side surface of the groove 573 or the protrudingportion 575 forms an angle of 45 degrees in the slanted direction Z andthe length of the bent portion is slightly longer, so that a positivesingular point of the liquid crystal may be easily formed.

A process of forming an opposite substrate in this embodiment issubstantially identical to the process of forming an opposite substratedescribed in FIG. 7A, FIG. 7B, and FIG. 7C. Also, a process of forming adisplay panel 400 in this embodiment is substantially identical to theprocess described in the first exemplary embodiment. Accordingly, anydetailed explanation will be omitted.

FIG. 9 is a plan view illustrating a display panel 600 according to athird exemplary embodiment of the present invention.

Referring to FIG. 9, a display panel 600 in this embodiment issubstantially identical to the display panel 100 described in FIG. 1,FIG. 2, FIG. 3, FIG. 4, FIG. 5, FIG. 6, FIG. 7A, FIG. 7B, and FIG. 7Cexcept that a groove 673 and a protruding portion 675 are formed in analternating arrangement through a second slit portion 671 formed througha pixel electrode 670 on an array substrate to have a convex and concavepattern. Accordingly, the same reference numerals will be used to referto the same elements as those described, and any detailed explanationwill be omitted.

A display substrate in this embodiment is substantially identical to anarray substrate 101 described in FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5,and FIG. 6 except that a groove 673 and a protruding portion 675 areformed in an alternating arrangement through the second slit portion 671formed through the pixel electrode 670 to have a convex and concavepattern. Accordingly, the same reference numerals will be used to referto the same elements as those described, and any detailed explanationwill be omitted.

Also, a groove 673 and a protruding portion 675 formed in an alternatingarrangement at edges facing each other of the second slit portion 671formed through the pixel electrode 670 are substantially identical to amanner and the shape of a groove 773 and a protruding portion 775 of thefirst slit portion 771 formed through the common electrode 770.Accordingly, any detailed explanation will be omitted.

As shown in FIG. 9, a groove 773 formed through the first slit portion771 and a protruding portion 675 formed through the second slit portion671 may be adjacent to each other. Also, a protruding portion 775 formedthrough the first slit portion 771 and a groove 673 formed through thesecond slit portion 671 may be adjacent to each other.

FIG. 10A, FIG. 10B, and FIG. 10C are cross-sectional views illustratinga process for manufacturing the array substrate 601 of FIG. 9.

A process of forming the opposite substrate in process of forming adisplay panel of the present exemplary embodiment is substantiallyidentical to the process of forming an opposite substrate 105 describedin FIG. 7A, FIG. 7B, and FIG. 7C. Accordingly, any detailed explanationwill be omitted.

A process of forming the array substrate 601 in process of formingdisplay panel of the present exemplary embodiment is identical to aprocess of forming a display substrate of the present exemplaryembodiment, that is, a process of forming the array substrate 601.

To manufacture a display substrate in the present exemplary embodiment,that is, the array substrate 601, as shown in FIG. 10A, a gate metallayer is deposited via a sputtering process on the lower substrate 603,and is patterned by photolithography method to form the gate line 611,the gate electrode 612, and the maintenance electrode 631.

Then, a gate insulation layer 619 is formed on the lower substrate 603.A semiconductor layer and a source metal layer are deposited. Then, thesemiconductor layer and the source metal layer are patterned to form thesemiconductor pattern 642, the data line 621, the source electrode 641,and the drain electrode 645.

Then, as shown in FIG. 10B, an insulation layer of organic material isformed on the lower substrate 603 having the data line 621 formedthereon. The insulation layer is patterned to form an insulation layer660 having the contact hole 661 that exposes the bent portion of thedrain electrode 645 and the stepped groove 665 that is formed in aportion of the insulation layer 600 corresponding to the maintenanceelectrode 631.

Then, an optically transparent and electrically conductive material isdeposited on the insulation layer 660 to form a pixel electrode layer.As shown in FIG. 10C, the pixel electrode layer is patterned to form thepixel electrode 670 having a second slit portion 671 formedtherethrough.

Finally, a lower alignment layer 602 is formed on the lower substrate603 having the pixel electrode 670 formed thereon to form the arraysubstrate 601.

Then, the opposite substrate and the array substrate 601 manufactured bya process described in FIG. 7A, FIG. 7B, and FIG. 7C are combined.Liquid crystal is interposed between the opposite substrate and thearray substrate to form the display panel 600.

FIG. 11 is a plan view illustrating a display panel 800 according to afourth exemplary embodiment of the present invention.

Referring to FIG. 11, a display substrate in this embodiment, that is,an opposite substrate is substantially identical to the oppositesubstrate 105 described in figures FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG.5, FIG. 6, FIG. 7A, FIG. 7B, and FIG. 7C except for the shape of agroove 973 and a protruding portion 975 formed on the first slit portion971. Thus, the same reference numerals will be used to refer to the sameelements as those described, and any detailed explanation will beomitted.

In this embodiment, a common electrode 970 of the opposite substrate hasa first slit portion 971 formed therethrough, and the edges of the firstslit portion 971 face each other, as described above, and have a groove973 and a protruding portion 975 corresponding to the groove 973 Thegroove 973 and the protruding portion 975 have a triangular shape. Aplurality of the grooves 973 are formed through one of the edges, aplurality of the protruding portion 975 facing the groove 973 are formedon the other edge facing the edge. Alternatively, the groove 973 and theprotruding portion 975 may be formed in an alternating arrangement on afirst edge, the protruding portion 975 and the groove 973 may be formedin an alternating arrangement on a second edge pairing with the groove973 and the protruding portion 975 on the first edge.

In this embodiment, side surfaces of the groove 973 and the protrudingportion 975 substantially form an angle of about 45 degrees in theslanted direction Z extended from the first slit portion 971. That is,the groove 973 and the protruding portion 975 may have a right isoscelestriangular shape.

When this embodiment is compared with the first exemplary embodiment inwhich a side surface of the protruding portion 275 forms an angle ofabout 90 degrees in the slanted direction Z, it is recognized that thestability of generating a singular point of the liquid crystal in apredetermined position is similar to the first exemplary embodiment.

A process of forming an opposite substrate in this embodiment issubstantially identical to the process of forming an opposite substratedescribed in FIG. 7A, FIG. 7B, and FIG. 7C. Also, a process of forming adisplay panel 800 in this embodiment is substantially identical to theprocess described in the first exemplary embodiment. Accordingly, anydetailed explanation will be omitted.

A display panel 800 in this embodiment is substantially identical to thedisplay panel described in FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5, FIG.6, FIG. 7A, FIG. 7B, and FIG. 7C expect including the opposite substratedescribed in FIG. 1. Accordingly, the same reference numerals will beused to refer to the same elements as those described, and any detailedexplanation will be omitted.

FIG. 12 is a plan view illustrating a display panel 1100 according to afifth exemplary embodiment of the present invention. FIG. 13 is across-sectional view taken along line II-II′ of FIG. 12.

Referring to FIG. 12 and FIG. 13, a display panel 1100 of the presentembodiment is substantially identical to the display panel 600 describedin FIG. 9, FIG. 10A, FIG. 10B, and FIG. 10C except that a pixelelectrode 1170 formed on array substrate 1101 further includes a firsthole 1177, and a common electrode 1270 formed on opposite substrate 1105further includes a second hole 1277. Accordingly, the same referencenumerals will be used to refer to the same elements as those described,and any detailed explanation will be omitted.

In this embodiment, the pixel electrode 1170 further includes the firsthole 1177 formed therethrough. The first hole 1177 is formed between theedges facing each other of the first slit portion 1271 formed throughthe common electrode 1270, and corresponds to the center of a groove1273 or a protruding portion 1275 of the first slit portion 1271 in theslanted direction Z. The first hole 1177 has a size smaller than thewidth of the first slit portion 1271.

In this embodiment, the common electrode 1270 further has the secondhole 1277 formed therethrough. The second hole 1277 is formed betweenthe edges facing each other of the second slit portion 1171 formedthrough the pixel electrode 1170, and corresponds to the center of agroove 1173 or a protruding portion 1175 of the second slit portion 1171in the slanted direction Z. The second hole 1277 has a smaller diameterthan the width of the second slit portion 1171.

A process of forming an opposite substrate 1105 in this embodiment issubstantially identical to the process of forming an opposite substratedescribed in FIG. 7A, FIG. 7B, and FIG. 7C except that the first slitportion 1271 is formed with the second hole 1277 on the common electrode1270, and a process of forming a display panel 1100 in this embodimentis substantially identical to the process of forming an array substrate601 described in FIG. 10A, FIG. 10B, and FIG. 10C except that the secondslit portion 1170 is formed with the first hole 1177 on the pixelelectrode 1170. Accordingly, any detailed explanation will be omitted.

In this embodiment, the upper alignment layer 1202 has a groove formedcorresponding to the first hole 1177, and a negative singular point isgenerated by the groove on a liquid crystal layer 1108 of the first hole1177. The lower alignment layer 1102 has a groove formed correspondingto the second hole 1277, and a negative singular point is generated bythe groove on a liquid crystal layer 1108 of the second hole 1277.Accordingly, a positive singular point is formed on the bent portion ofthe first slit portion 1271 and the second slit portion 1171. A negativesingular point is definitely formed by the first hole 1177 and thesecond hole 1277 between the bent portions. Thus, stability may beimproved so that a singular point of the liquid crystal may be generatedat a predetermined position.

FIG. 14 is a cross-sectional view showing a display panel 1400 accordingto a sixth exemplary embodiment of the present invention.

Referring to FIG. 14, a display panel 1400 of this exemplary embodimentis substantially identical to the display panel 600 described in FIG. 9,FIG. 10A, FIG. 10B, and FIG. 10C except that a first protrusion 1477,instead of a first hole, is formed on the pixel electrode 1470 of arraysubstrate 1401 and a second protrusion 1577, instead of a second hole,is formed on a common electrode 1570 of an opposite substrate 1405.Accordingly, the same reference numerals will be used to refer to thesame elements as those described, and any detailed explanation will beomitted.

In this embodiment, the first protrusion 1477 is formed on the pixelelectrode 1470. The first protrusion 1477 is formed between the edgesfacing each other of the first slit portion 1571 formed through thecommon electrode 1570, and corresponds to the center of a groove or aprotruding portion of the first slit portion 1571 in the slanteddirection Z. The first protrusion 1477 has a size smaller than the widthof the first slit portion 1571.

In this embodiment, the second protrusion 1577 is formed on the commonelectrode 1570. The second protrusion 1577 is formed between the edgesfacing each other of the second slit portion 1471 formed through thepixel electrode 1470, and corresponds to the center of a groove or aprotruding portion of the second slit portion 1471 in the slanteddirection Z. The second protrusion 1577 has a diameter smaller than thewidth of the second slit portion 1471.

In a process of forming an opposite substrate 1405 and a process offorming a display panel 1400 of the present invention, a transparentconductive layer such as ITO or IZO is patterned by photolithography toform the first slit portion 1571 on the common electrode 1570, and toform the second slit portion 1471 on the pixel electrode 1470. Forexample, a portion of a photoresist layer etched to form the first slitportion 1571 and the second slit portion 1471 remains to form the firstprotrusion 1477 and the second protrusion 1577. Thus, a process offorming the first protrusion 1477 and the second protrusion 1577 is notsupplemented. A process of forming a display panel 1400 in theembodiment is substantially identical to the process of forming anopposite substrate 105 described in FIG. 7A, FIG. 7B, and FIG. 7C and anarray substrate 601 described in FIG. 10A, FIG. 10B, and FIG. 10C exceptfor forming the first protrusion 1477 and the second protrusion 1577.Accordingly, any detailed explanation will be omitted.

In this embodiment, it is recognized that a negative singular point isgenerated by the first protrusion 1477 and the second protrusion 1577 ona liquid crystal layer. Thus, a positive point is formed on bentportions of the first slit portion 1571 and the second slit portion1471. A negative singular point is definitely formed by the firstprotrusion 1477 and the second protrusion 1577 between the bentportions. Thus, stability may be improved so that a singular point ofthe liquid crystal may be generated at a predetermined position.

FIG. 15 is a cross-sectional view showing a display panel 1700 accordingto a seventh exemplary embodiment of the present invention.

Referring to FIG. 15, a display panel 1700 and a process of forming thesame in this embodiment is substantially identical to the display panel1400 and a process of forming the same described in FIG. 14 except thata second hole 1877, instead of a second protrusion, is formed in thecommon electrode 1870 of the opposite electrode 1705. Accordingly, thesame reference numerals will be used to refer to the same elements asthose described, and any detailed explanation will be omitted.

In this embodiment, a first protrusion 1777 is formed on the arraysubstrate 1701, and the second hole 1877 is formed on the oppositesubstrate 1705. Alternatively, a first hole may be formed on the arraysubstrate 1701, and a second protrusion may be formed on the oppositesubstrate 1705. In addition, the first hole and the protrusion may beformed on the pixel electrode 1770 in an alternating arrangement or thesecond hole and the second protrusion may be formed on the commonelectrode 1870 in an alternating arrangement.

In this embodiment, a positive singular point is formed on bent portionsof a first slit portion 1871 and a second slit portion 1771, the firstprotrusion 1777 is formed on the pixel electrode 1770 between the bentportions, and the second hole 1877 is formed through the commonelectrode 1870. Accordingly, a negative singular point is definitelyformed. Thus, stability may be improved so that a singular point of theliquid crystal may be generated at a predetermined position.

It will be apparent to those skilled in the art that variousmodifications and variation can be made in the present invention withoutdeparting from the spirit or scope of the invention. Thus, it isintended that the present invention cover the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. A display substrate comprising: a base substrate having a pixel areawith a horizontal side and a vertical side; and a transparent electrodedisposed in the pixel area and comprising a plurality of slit portionsextending in a slanted direction with respect to the horizontal side andthe vertical side, wherein a first edge of the slit portions comprises afirst groove and a first protruding portion that are alternatelyarranged, the first protruding portion being defined by adjacent firstgrooves, and wherein a second edge of the slit portions faces the firstedge and comprises a second protruding portion corresponding to thefirst groove and a second groove corresponding to the first protrudingportion, the second protruding portion and the second groove beingalternately arranged.
 2. The display substrate of claim 1, wherein alength of the first groove in the slanted direction is longer than alength of the second protruding portion, and a length of the secondgroove is longer than a length of the first protruding portion.
 3. Thedisplay substrate of claim 2, wherein the first groove and the secondgroove and the first protruding portion and the second protrudingportion are respectively arranged to have a depth and a height, and aninterval distance between the first groove and the second protrudingportion is the same as an interval distance between the second grooveand the first protruding portion.
 4. The display substrate of claim 3,wherein an angle between a side surface of the first protruding portionand the first groove and an angle between a side surface of the secondprotruding portion and the second groove are at least one of 45 degreesor 90 degrees.
 5. The display substrate of claim 4, wherein the firstprotruding portion and the second protruding portion have at least oneof a rectangular shape, a trapezoidal shape, and a triangular shape, thefirst groove and the second groove being arranged along the secondprotruding portion and the first protruding portion, respectively. 6.The display substrate of claim 3, wherein the height of the firstprotruding portion and the height of the second protruding portion areeach 2 μm to 4 μm.
 7. The display substrate of claim 2, wherein the slitportions are symmetrical with respect to a center line of thetransparent electrode, the center line being parallel to the horizontalside.
 8. The display substrate of claim 2, further comprising: a colorfilter disposed between the base substrate and the transparent electrodeand corresponding to the pixel area; and an overcoating layer disposedbetween the color filter and the transparent electrode.
 9. The displaysubstrate of claim 2, further comprising: a switching element comprisingan output terminal connected to the transparent electrode, disposedbetween the base substrate and the transparent electrode, andcorresponding to the pixel area; a data line connected to an inputterminal of the switching element; and a gate line connected to acontrol terminal of the switching element.
 10. A display panelcomprising: an array substrate comprising a lower substrate, a switchingelement arranged on the lower substrate, a signal line connected to theswitching element, and a pixel electrode connected to an outputelectrode of the switching element; an opposite substrate comprising: anupper substrate having a pixel area with a horizontal side and avertical side; and a common electrode comprising a plurality of slitportions extending in a slanted direction with respect to the horizontalside and vertical side, wherein a plurality of grooves and a pluralityof protruding portions defined by the grooves are alternately arrangedin edges facing each other of a first slit portion so that the firstslit portions have a zigzag pattern shape defined by the groove and theprotruding portion; and a liquid crystal layer being arranged betweenthe array substrate and the opposite substrate, to be vertically alignedwith respect to the array substrate and the opposite substrate.
 11. Thedisplay panel of claim 10, wherein the groove and the protruding portionare respectively arranged in a uniform depth and height, and an intervaldistance between the groove and the protruding portion is substantiallyuniform.
 12. The display panel of claim 11, wherein the height of theprotruding portion is 2 μm to 4 μm, and an angle between a side surfaceof the protruding portion and the slanted direction is 90 degrees or 45degrees.
 13. The display panel of claim 11, wherein the pixel electrodefurther comprises a first hole formed therethrough, the first holehaving a smaller diameter than a width of the first slit portion, beingdisposed between edges of the first slit portion facing each other, andcorresponding to a center of the groove or the protruding portion in theslanted direction.
 14. The display panel of claim 11, wherein the pixelelectrode further comprises a first protrusion arranged thereon, thefirst protrusion having a smaller width than a width of the first slitportion, being arranged between edges of the first slit portion facingeach other, and corresponding to a center of the groove or theprotruding portion in the slanted direction.
 15. The display panel ofclaim 11, wherein the opposite substrate further comprises: a colorfilter disposed between the upper substrate and the common electrode tocorrespond to the pixel area; and an overcoating layer disposed betweenthe color filter and the common electrode.
 16. The display panel ofclaim 11, wherein a second slit portion is arranged through the pixelelectrode, the second slit portion extending in the slanted directionand being arranged between the first slit portions.
 17. The displaypanel of claim 16, wherein a groove and a protruding portion arearranged in an alternating arrangement at edges of the second slitportion facing each other, and a length of the protruding portion facingthe groove is smaller than the groove in a slanted direction.
 18. Thedisplay panel of claim 17, wherein the first slit portion is symmetricalwith respect to a center line that is parallel to the horizontal side.19. The display panel of claim 18, wherein bent portions of the firstslit portion and the second slit portion are bent parallel with thehorizontal side or the vertical side.
 20. The display panel of claim 19,wherein an outward edge of the bent portion of the first slit portionand the second slit portion is connected to the protruding portion, andan inward edge of the bent portion is connected to the groove.
 21. Thedisplay panel of claim 17, wherein the common electrode furthercomprises a second hole formed therethrough, the second hole having asmaller diameter than a width of the second slit portion, being arrangedbetween edges of the second slit portion facing each other, andcorresponding to a center of the groove or the protruding portion in theslanted direction.
 22. The display panel of claim 17, wherein the commonelectrode further comprises a second protrusion arranged thereon, thesecond protrusion having a smaller width than a width of the second slitportion, being arranged between edges of the second slit portion facingeach other, and corresponding to a center of the groove or theprotruding portion in the slanted direction.
 23. The display panel ofclaim 16, wherein the array substrate further comprises an insulationlayer disposed between the pixel electrode and the switching element,wherein the insulation layer has a contact hole exposing a portion ofthe output electrode of the switching element, and the contact holecorresponds to the protruding portion of the first slit portion or acenter portion of the protruding portion in the slanted direction. 24.The display panel of claim 23, wherein the array substrate furthercomprises a maintenance electrode disposed to correspond to the centerline, which is parallel to the horizontal side, between the lowersubstrate and the insulation layer to maintain a pixel voltage appliedto the pixel electrode, and a stepped groove is further arranged in theinsulation layer to correspond to a crossing area in which the firstslit portion and the second slit portion cross each other and themaintenance electrode.